#include <iostream>
#include <stdlib.h>
const double PI = 3.14;

void caculateCircle(void)
{
    double semidiameter, myarea, myround;
    std::cout << "Please input a semidiameter:" << std::endl;
    std::cin >> semidiameter;
    myarea = semidiameter*semidiameter*PI;
    myround = semidiameter*2*PI;
    std::cout << PI << std::endl;
    std::cout << "Area is \n" << myarea << std::endl;
    std::cout << "Roud is \n" << myround << std::endl;
}

int main(int argc, char const *argv[])
{
    caculateCircle();
    return 0;
}
